With 50,000 patients undergoing open-heart or coronary bypass surgery anually and the number growing each year, there is a pressing need for a longitudinal study of post-operative recovery of these cardiovascular patients. The proposed multidisciplinary project, heavily weighted toward the behavioral sciences, is designed in an effort to overcome limitations of past studies. We propose to follow, at semi-annual intervals for three years, 1200 to 1400 patients who have undergone coronary artery bypass or cardiac valve surgery. Recovery and rehabilitation will be defined comprehensively in specific, operational terms relating to medical status, fulfillment of occupational and family roles, social participation, emotional state, perceptions and feelings related to one's own cardiovascular illness and surgery, activities of daily living, and self-esteem. Predictor variables include existing and to-be-developed scales for longstanding personality traits, emotional states, specific disease-related experiences, sociological factors, and life changes. A variety of biomedical measures are included as predictor, control, and outcome variables. Plans for recruitment of the study group, and the collection, management and analysis of data are presented. This study represents a collaborative effort of the Boston University School of Medicine and Mended Hearts, Inc., an international organization of cardiac surgery patients. It seeks to fill gaps and resolve inconsistencies in the knowledge of the process of recovery and rehabilitation from major heart surgery, and thus holds promise of building foundations for more comprehensive post-surgical care programs and hence more complete rehabilitation for a greater proportion of a growing population of heart surgery patients.